Two-stroke internal-combustion engine



Nov. 4 1924.

J. LEROY TWO-STROKE INTERNAL COMBUSTION ENGINE Filed July 10 1920 6 Sheets-Sheet l a w W a mu 5 J Nov. 4 1924. 1,514,057 I JQLR-EROY- TWO-STROKE INTERNAL COMBUSTION ENGINE Filed July 10, 1920 6 Sheets-Sheet 2 J. LEROY TWO-STROKE INTERNAL COMBUSTION ENGINE Filed July 10,

1920 6 Sheets-Sheet 5 Nov. 1924. 1,514,057

' J. LEROY 'LWO*STROKE INTERNAL COMBUSTION ENGINE 6 SheetsSheet L Nov. 4 1924 1,514,057 I J. LEROY TWO-STROKE INTERNAL COMBUSTION ENGINE Nov. 4 1924a 1,514,057

J. LERQY TWOSTROKE INTERNAL COMBUSTION ENGINE Filed July 10, 1920 6 Sheets-Sheet 6 fin e2? 50/ 415 id/" ay Patent d 4,?i924.

'ternal Comb'ustion Engines, of which the following is wspecifiatiom;

The invention may "have various industrial applications (automobile, aviation, inarine and other purposes), and it includes the scavenging hy'compressed air, the admission i of the-explosive mixture hy'compression, thestarting by compressed air, the pneumatic further, includes aspecial distribution mechanism for the'motor and for the pump I ensuring the control of the said distribution mechanism. III-order to render intelligible thedescription of-th'e said invention; it is represented in the accompanying drawings as follows;

Fig. lx'shows a'transvcise selrtion through the-axisof a cylinder. F ig.'2 shows a longitudinal section through the axis of the engine. Fig; 3-is a view in Yelevation'of the engine on the exhaust side.

.Fig. 4 is a view inelevation of the engine on the admission side.

Fig; shows a sectional elevation of-a ..n loditied construetion of the system "accord- I ing to the presentinvention.

Fig. (3 shows a detailed view on the line JJVl-Vl (iii-Fig. 8 and represents the distributors applied respectively to the motor and to the pump.

-l"i 7 shows a detailed view of one of the elements ol these distributors.

i Fig-7 shows a swrtionnl elevation of the upper purl of a modilieation in the eonslrn tion ol the motor.

Fig. 9 shows a sWt-ional elevation at an anglwol fill) in regard to Fig. 9 of his modilieat'ion. 'l'he Figures vi to l show a \"limler l pr \id d with two compr ssion rha nhers :2. 7 and in \vhieh theinolor piston l travels. (onneeled by means of a hollow shaft 5 to a pis- -Ion pump (3 serving as a sliding guide and "travelling in the body of the pump 7. 'lllis pistmrpnrnp (3 is eonnected' in turn lgyqneuns Q?" pfi izilfdevices-ior actuating the parts IIED ST T'H iS JULES LEROY, or rARIs FRA CE;

Wmsrnox'ia INTERNAIfCQMBUSTIONIlNGIiNE.

Application filed ma 10, 1920'. Serial No. 355,333. g

The crankshaft 9 is "enclosed in agear (this it wheel can be dispensed withinihe,

case 0 a three cylinder machine .and at .the othe'r, enda spur-pinion 13 w ich con-' trols the distribution by meansiof the chain .wjater pump '17. The gearease '11 is conbraking'of' the motor; -the said invention,

nected. rigidlyto the mbtor block by means which render the fixture secure, enclosing and holdin "fast between them as :a' fixture the pump Ody-'7 and therplugs QO. -.The.,-

cylinder bloclt 'is surrounded by. a circulalting water supply 21 the chamber .forwhioh. is closed at itsupp ertpart by,means of the cover- 22 secured inplace by the-studs'fl23r-"T Betweenthe cylinder block and the pump body the plugs are interposed forgthe water circulation and they form the-bottom of the cylinder for the lower'explos ion ehambr 3.

The said bottom is moreover provided WVlthf the .stufiing'box 24 about which it forms a tight joint for the passage .of the piston rod 5.

Midway the ends ofeach n'iotor cylind'er 1 is arranged the ekhaust port 25 connecting with a passage 26 closed inits course along-- side the cylinder block. by a -coverpla'te 27. Each eompres'sion chamber 2, is provided with a sparkingTpIugQS.'29 "whichgives one spark at each stroke and with, an admission the braking.

"ot a rod 8 to one of the cranks of the el'anhvalve 30. '31. controlled by a "cam 32 keyed .upon the shaft 33. This cam puts 'the cylinder 1 into comnn nication with the passage 3435' (leading to the carburettor once at each revolution of the crankshaft).

lhe lulirication of the cylinder is ensured' by an oil supply under pressure through the tuhivfhi. The tubes 37. leading from the chamber 38. serve for the scavenging and for the starting by the compressed air. They correspond toindependent'chamhers. eaeh'of which has a valve 39' controlled by a ram 40 for the scavenging and 41 for the start ing. The compressed air necessary for these actions ar'rives from the high pressure reservoir 42, through a tube 43 andmay be retained in case of need; this re'sez ivoir is supplied from the pumps 7 at the mo ent of The cam shaft 33 is supportedby suitableuprights and in the interior of thisshaft there. is placed anotherupon which are keyed the starting and scavenging cams 41 and 40, which shaft can be displaced by. sliding v 'in o'rder to set the cams above mentioned at-any moment required over against the"va'lves'39.

q Upo' *the pump body 7 is fixed a collec- '6 tor 44 aving in the axis of each pump an Y .automatic suction valve 45, and a compression valve;46 this latter valve can be fixed upon its seat at the moment of the braking bymeans of a cylindrical axis 47fbearing a locking cam. 48. and -controlled by a lever i 1 49. This collector is in communication with the low pressure reservoir 50 which'supplies air to'the. carburettor; this low pressure reservoir provided with a safety valve 51 and an 'air inlet 52 forthe scavenging. Upon the main collector 44 is fixed a lit-- tle secondary collector 53 for the collection gof comprejssed air (hiring the/braking, (at 1 which time the valves 46'avre'closed); f This 7 o'secondary collector is provided with inlets closedin normal working by ball valves 54,. gf mid inlets whenopened placing each pump,

vbody -7 in'icommunication with "the collector 53; the 'said collector is aLsoin-coxmnw nication, by. means of the tube 55, with thehigh pressure reservoir 42 which has an out- 1 let plug and a safety valve 56; reservoir 42 is connectedito the valves 39 "by the pipe 43.

. The petrol reservoir'58 is also'under pressure. The carburettor 59 is adjustably con nected to the pipes 34 held in place against the cylinder block by a'holder 60.

f The normal operation of the motor is asfollowz" Taking the motor at thepoint at which it'is shown in Fi res l and 2,, at this no "ment the motor p ston 4i's at the upper dead point (the motor rotates to the rightin the directionof the hands of a watch) and the $0 spark which has been producedby' the upper sparking plug 28 several millimetres before the end of the stroke has ignited the charge which was compressed in the explosion chamber 2; the motor piston 4 is driven towards the bottom of its course, carrying with it the pump piston 6, which draws in fresh air from outside for two cylinder charges by means of the automatic valve 45.

The motor piston 4, on descending, has uncoveredthe 'outlet'port 25 through which the. burned gases escape 'as soon as these are nearly discharged, the cam 40 opens the cavenging valve 39 and non-carbureted compressed air reaches the cylinder through the pipe 37- and sweeps out the remaining burned gases.

y The same result may be obtained. by

means of the starting cam 41, the compress ed air in either case remaining in the pipe 50 37 until the pressure has fallen in the inte- -rior of the cylinder 1 to allow it to penetrate into this latter. The scavenging has for its .object to separate the entering charge from the escaping charge, and to cool the end of the inoter piston 4 and the cylinder. When obtain this result the engine cy #BE-sT AvAlLA-B LE cos? the burned gases are completely discharged,

thecam 32 operates in its turn the admission valve 30, which puts the'channel 34 contraining the carbureted gas into communical tion with the cylinder 1; the cylinder fills '0 with explosive mixture (the scavenging valve 39 having been-closed shortly before I the opening of the admission valve '30) and the admission valve 30 remains raised during the rise 'ofthc pistonhntil this latter 7 has again closed, by'covering it, the exhaust port 25 so as to ensurea charge as complete f as possible. The admission valve 30 must not return to its seat until the gases have no further momentum and tend to flow hackinto the channel 34. The piston continuing to rise, the compression continues and tenninates'at the-upper dead point; 'theignition occurs I'a little before this point is reached as pleviouslyjexplained and the cy-Q 5 cle continues. f The saine sequence occurs exactly at the other end offthe, piston, but delayed 180.. Durin ithis-tim t e pump piston has risen, the valve 45 has been closed,-th airhas been. forced vintbthe"collector 44, has *paa'sed through. the back; pressure valve 46 and has frewchedthedow' pressure reservoir 50,,

.Thesecond and the third cyli ders oper ate in like manner but] with" a respective de I lay as againstthe cylinder of 120;and. 240?{infothen-wordshs there are two'e rplosions per cylinder and per revolution, one explosion takes plaoeat every 60. To

supplied with carburetted gas 'as follows The air drawnin by the pump 7 is forced through the collector 44 into the low pmsure reservoir .50 which is placed in communication. withlthe passa e 34, distributing the air passing throng the jet of they carburettor. .1 p

This carburetted mixture is then distributed to the engine cylinder 1,' passing through the channels 34', 35 and the control valves 30,31 at the required moment, as-has been already explained. 1

WVhen the lever 49,- is actuated to operate the locking cam 48'of the shaft 47, the. said cam closes the back-pressure valve 46 and the air drawn in by the pumps 7 is compelled, in order to escape, to raise the ball 54 and to pass through the collector 53, which delivers it to the high pressure reservpir 42.

This air which hasbeen thus stored up'is intended to serve for starting the motor.

In fact if, meansof a valve the air of the reservoir 42 is allowed toflo into the tube 37, it passes to the valves 39, one of .which controls admission of the air to the compression chamber 2 and the cam 40' of the shaft 33 causing the raising of this valve 21 little after the passage of the upper dead point of the motor piston r 4, the compressed air can flow through nder 1 is 1002 T 3M m eri the tube 37 and arrive in the com ,pression chamber2 whence it'forcesthe P137 lton t'towards the lower dead point, thus starting the motor. The carbureted air be I in distributed at the same time: to the- ,as the engine turns uiclry 1 closing the valve p cy inders 1,.theexplosions take place as soon enough to cause the-magneto to give a su cie'ntlyhot spark.

The engine having started it is only needful to'shut-ofi' the high ressure air'passage byl upon the supply r tubeuto'theeylindenqf way would not be sufficient. The raking is obtained by tuning, by

-means' of ,a eonplingbar, all the levers 49 of the collector 44, which action causes the closing ofthe compression valves 46 by means-of the locking cams 48 of the cvlindrical shafts-47, When this result is at- ,tained, the air drawn'fini by the pumps is compelled, in order; to escape, to pass through the little secondary collector 53,

' lifting the ball valve 54.

For the re-charging of the high pressure reservoir 42, the "operator can produce the effect, either with the upper cylinders or with the lower cylinders, simply by closing one of the delivery valves to the cylinders of the tubes 34. a i

a Thepresent invention comprises a, inodification lncluding hemispherical compression chambers,'wlnch involves the provision of special distributors for the motor and for v the pump. Each of these distributm's comprises a slceve'92 concentric to the pump cylinder. (Figs. 5, 6, 7.)

This sleeve is'providcd with'rollers 93 ar- [face and bein'g conformedsoas to ensure ranged at regular intervals around'its axis, and rotating in a track on the incline 94 the height of which is equal to the course which the sleeve 92 is arranged to take.

The aforesaid sleeve is moreover provided with a projection 92 co-operating with the circular half-teeth 92 made in one piece with a rod 95 which can rotate on its axis. This rod 95 is controlled by a connecting piece 96 co-operating with a cam 97 keyed upon a shaft-big 98 which receives its motion from the main shaft 73 by means of the cone gears 99.

The operation of the mechanism above described is as follows: i I

The cam 97 acting upon the member 96 pushes 'therod 95 which in turn by means of the half-tceth'QQ and the tooth 92" causes the sleeve to mm; During this rotation the rollers 93 travel upon the inclines 94 imparting thus to the sleeve a risingmotion.

The combination of these two controls resuits in giving to the sleeve, a rising hel1- ooidal IUOtlOIl.

.jnalfstarting q nt..,.. Another; ea 'reoffthe,

air; pump.

, W 'ishigh'pressnreair can alsoserve fofi thefscavengin after having passed through V the cases in which the air from w 3 the low. pressure reservoir 50 used ljfitllc alternately a pump stroke .mtqf ordina sure reservoir;

trolling the dis'tributor'of ,the,conipressori I A spring 100 returns the sleeve to its ()llgldescribed consists in t joperat'i'on of thc -.Y Theair pump 101' draws in. the on through the openings 102, and .forc the said air through thecO'nduit {103 iiit-o ithe gear box which communicates tih g t a glngthecase ofa sm e y isone .ofsimple effect and! er box and a pump stroke into 'tlr In order, to'fo k alternate pump strokes one first can "the a pump 101m drau' inj'norrnallyfhlit'leaving' 85 the compression port's 107. closed iair in order'to escape is obligedt the resistance of the 'valve lQsf andf into the high pressure rse'rvliirtl on pipe 109'; The next stroke. of ,th given in' ordinary wurse an'd l so? for the purpose of enabling jitf 'tofa t double effect like the 'motorcylind'erj the following arrangement is adopted 8 The shape ofthepiston 165 is shown n e the drawing and the "lower" compressiiih chamber 166 has 'corre'spondihglya "li nder bottom 167,

outlet 169 are doubled likewise tlie dis- 10d l'ributors' 1170 I'll, the Suction""tuhesd 112, 17 3 and .thc "compression tu'bcs "1 74, 175. Each of the distributors 170, 17 1' is "controlled by a corresponding cam 176,'-177 one at. least of-'-'thcse-cams havh'iga slopin'gisurthe stoppage 'as the dead point of tl edistrlbutor which it controls 4 This improved -construction ofwthc air pump is of particular interest in the case is, displaeed,.together with the cam .con-

trolling the distributor of the upper cylinder and the cam controlling the injector delivering the fuel in the same cylinder, all these .cams being rigidly connected tot the rod 179.

1G and a lesser boss's, and gives on one stroke In this manner, there can be put into operation, at will,;;"one or the other of guides a ora'of am'176, and herb of cam 177.

Theupper guides a and]; of these two cams present 'two bosses fa, and. a and the cam turning with I. speed one half that ofthe ,metor-sliaft, the distributors 170 and 171 (Fig. 8) would have a'movement' ofthe same frequency as that of the pistons. The

no boss, and corresponds to complete imbut insuflicient toguide a presents a'single normal-boss out of two, to distributor 170,1 movement of full amplitude; and, on one stroke out of two, a movement of reduced amplitude,

sufiicient for opening the admissionport, n the outlet port. Also, theg'uide b of t e lower cam, presents mobility of the distributor 171, in the pogiven-to cams- 176, and 177, by the mech-' anician, to make the motor function in the sitionof opening of the inlet ports.

It is ossible, according to the positions following difierent manners. When. the cams to the rollers of t e distributors 170' and 171, the pump isdoubled acting, pumping air at low pressureonlg.

When guides a'- an bare in operation, in the same manner as pressure onl the upper face has a mixed function. ne stroke out of two pumps low pressure, and the following stroke, high pressure. On the first stroke, when boss 0' acts, d1stributor'170 goes to the end of .its movement, and o ensthe port 169, by which the compresse air passes to the low ressure container. On the next stroke, the

- ow boss 0 comes into action, and first opens the inlet port 168, but does not reach outlet port 169. Air is thus highly com pressed, until it attains sufficient-pressure to raise an automatic valve, $11M; shown, but similar to 108 of Fig. 5) w ich communicates with. the high pressure container. Thus the operation is, on one stroke out of two, high pressure and the next, lowpressure.

hen guides a and b are in operation, the upper face of the pump piston has a mixed operation, while the lower face is without action, the lower inlet port 168, being kept closed. v

Finally, when guides a and b are in operation, the upper face-otthe piston, operates on low pressure only, the lower face being inoperative, because of the constant opening of the lower inlet port-168.

This capability of controlling the functioning of the motor, adapts itself to variable conditions of power and of air, and is of particular advantage where the motor is to be used in airplanes which must fly at variable heights. I

The special method of arrangement of resent guidesa and b above, (i. e; low' p a BESTAVAH-ABLECOPY the vertical shaft 98 forms also one oLthe features of my improved system. It controls, by means of suitable helicoidal gearing and 111 a shaft 112 which actuates the magneto and a water circulatinglp mp of known construction. The cam' s at 98 possesses in addition to the cam 97 which actuates the distributor ofthe pump the further cams 113 whichcontrol the distributors of the motor, the c'ams'114 which control the starting;-the cams-115 which control the admission of the -va ourizing air, and fimally thecams 116 whic the fuel. 4 The cam shaft 98 also ensures the control of the him 117 by the interposition =contr0l the injection of ofa conical .cou'pling 118, 119 with strong friction.

It. should also'be observed that the invention in uestion ensuresthe commencement of the admission of pure air intp the motor cylinder only at the moment when the escape of'the burnt gases is almost finished. It is only when the exit openings are masked by the piston that the petrol or other com-' bustible liquid arrives in the motor. w I Having now particularly described the nature of my said invention, and in what manner the. same is be performed, what 1. A two stroke, double acting, internal combustion engine, comprising, a motor is ton and a pump piston on a single r01, 1

low pressure air reservoir, for receiving ow pressure air for the known feeding and scav enging of the motor, a high pressure air reservoir for receiving high pressure air for I the known starting with compressed air, tlie pump piston being arranged, for feedin at times, the low pressure reservoir, an at times, the high pressure reservoir, a cut off means for the low pressure reservoir, change of feed from low pressure to'high pressure, being controlled solely by the operation of said cut off means.

2. A two-stroke double-acting internal combustion engine, comprising a pair of aligned cylinders, a motor piston in one of said cylinders, an air pump piston inthe other of said cylinders,-a piston rod connecting said pistons to operate in unison, and distributing means comprising a sleeve rotatably mounted upon the pump cylinder and provided on its periphery with rollers, inclined tracks for said rollers, and means for automatically rotating said sleeve one direction, whereby said rollers travelingupon said inclined tracks impart a rising motion to said sleeve.

3. A two-stroke double=acting internal combustion engine, comprising a pair of aligned cylinders, a motor piston in one ofmounted for rotation upon the pump cylinder, and provided upon its periphery with rollers, inclined tracks for said rollers, and means for rotating said sleeve in opposite directions, comprising a projection on said sleeve, a sliding rod having a pair of teeth cooperating with the projection on the sleeve, and means for reciprocating said rod in op osite directions. r

4. two stroke, double acting, internal combustion engine, comprising, a plurality of motor pistons, each of which has a double acting pump piston coupled therewith, a high and a low pressure air reservoir, for

- receiving air from the pump piston, distributors controlling the air for the pump pistons, said distributors being controlled by slidahly adjustable cams, each cam having whereby, the operation of the pump piston BEST AVAILABLE CO Y"- two appropriately formed guide portions,

can be controlled for double acting low pressure pum ing, for single acting low pressure and or single acting low ressure pumping on one of two strokes, and or highpressure pumping on the other, this latter being due to one of the distributors being stationary, and the other distributor opening an outlet port, on only one of the two strokes.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

'Witnesses:

' Armin; BonmLLoN. Jums FAYOLLEN JULES LEROY. 

